1. Field of the Invention
The present invention relates to a sheet process device which once stacks received sheets of paper (simply referred as xe2x80x9csheetsxe2x80x9d hereinafter) on a first stack means and then shifts the stacked sheets to a second stack means.
2. Related Background Art
Conventionally, a device consisting of a combination of a process tray and a stack tray has been known as a sheet process device used in an image formation apparatus such as a copy machine, a printer or the like. On the process tray, sheets are stapled according to necessity. On the stack tray, sheets are received and stacked each sheaf.
In this sheet process device, a stapler to staple the sheets and a jogger to adjust or align the sheets with movement in front and rear directions are provided on the periphery of the process tray. Sheaves of sheets are adjusted on the process tray, the adjusted sheaves are respectively stapled, and the stapled sheaves are then discharged to the stack tray by a pair of sheaf discharge rollers.
Then, the stack tray is moved in forward and reverse directions (i.e., sheet-width direction) for each sheaf to sort over the sheaves of sheets. Moreover, the stack tray can be moved in upward and downward directions to fit a sheet face to the discharge roller.
However, the conventional sheet process device has following problems, and thus solutions for these problems have been earnestly expected. That is, in case of discharging the sheaf of sheets (paper) not yet stapled, if such the sheaves stacked on the process tray in large quantities are discharge at a time, the sheaves of sheets on the stack tray are off the alignment, whereby it becomes difficult to sort the sheets.
Further, in order to avoid a situation that, while the sheaves of sheets not stapled yet and stacked on the process tray are discharged to the stack tray, next or following sheets are fed to the process tray, it is necessary to temporarily stop an operation of the image formation apparatus itself during the sheet discharge operation.
An object of the present invention is to provide a sheet process device which can solve the above conventional drawbacks.
Another object of the present invention is to provide a sheet process device in which sheaves of sheets can be discharged without the sheaves stacked on the stack tray being off the alignment.
Still another object of the present invention is to provide a sheet process device in which sheaves of sheets stacked on a process tray can be discharged to a stack tray without next or following sheets being fed to the process tray while the current sheets on the process tray are discharged and without an image formation apparatus itself being stopped.
In one embodiment, the sheet process device of the present invention comprises first stack means for stacking thereon discharged sheets, binding process means for performing a binding process on the sheets stacked on the first stack means, second stack means for stacking thereon the sheets transferred from the first stack means, and a transfer unit for transferring the sheets from the first stack means to the second stack means. In addition, the device comprises transfer control means for driving the transfer unit in a case where a last sheet of one group is stacked on the first stack means in a mode to perform the binding process by the binding process means, and for driving the transfer unit in a case where a predetermined number of sheets are stacked on the first stack means and where the last sheet of the group is stacked on the first stack means in a mode not to perform the binding process by the binding process means.
In another embodiment, the sheet process device of the present invention comprises stagnation means for stagnating received sheets, first stack means for stacking thereon the sheets, carrier means for carrying the sheets to the first stack means without stagnating them in the stagnation means, and carrying the sheets to the first stack means after stagnating them in the stagnation means, and second stack means for stacking thereon the sheets transferred from the first stack means. Further, the device includes a transfer unit for transferring the sheets from the first stack means to the second stack means, transfer control means for driving the transfer unit in a case where a predetermined number of sheets are stacked on the first stack means and where a last sheet of one group is stacked on the first stack means, and carrier control means for controlling the carrier means to cause the stagnation means to stagnate the sheets in a case where the transfer unit starts the sheet transfer. Additionally, the transfer control means drives the transfer unit in a case where a third last sheet of the group is stacked on the first stack means.
In yet another embodiment, the sheet process device of the present invention comprises stagnation means capable of stagnating B sheets received, first stack means for stacking thereon the sheets, carrier means for carrying the sheets to the first stack means without stagnating them in the stagnation means, and carrying together with newly received sheets the sheets to the first stack means after stagnating at least one of the sheets in the stagnation means, and second stack means for stacking thereon the sheets transferred from the first stack means. Further, the device includes a transfer unit for transferring the sheets from the first stack means to the second stack means, transfer control means for driving the transfer unit in a case where a predetermined number of sheets are stacked on the first stack means and where a last sheet of one group is stacked on the first stack means, and carrier control means for controlling the carrier means to cause the stagnation means to stagnate the sheets in a case where the transfer unit starts the sheet transfer. Additionally, the transfer control means drives the transfer unit when any one of the sheets B+1 to two-before-a-final-one of the sheets constituting the group is stacked on the first stack means.
In still yet another embodiment, the sheet process device of the present invention comprises stagnation means capable of stagnating B sheets received, first stack means for stacking thereon the sheets, carrier means for carrying the sheets to the first stack means without stagnating them in the stagnation means, and carrying the sheets together with newly received sheets to the first stack means after stagnating at least one of the sheets in the stagnation means, and second stack means for stacking thereon the sheets transferred from the first stack means. Further, the device includes a transfer unit for transferring the sheets from the first stack means to the second stack means, transfer control means for driving the transfer unit in a case where a predetermined number of sheets are stacked on the first stack means and where a last sheet of one group is stacked on the first stack means, and carrier control means for controlling the carrier means to cause the stagnation means to stagnate the sheets in a case where the predetermined number of sheets are stacked on the first stack means and where the last sheet of the group is stacked on the first stack means. Additionally, the carrier control means controls the carrier means to cause the stagnation means to stagnate at least a second last sheet of the group, irrespective of the carrier control.
In still yet another embodiment, the sheet process device of the present invention comprises first stack means for stacking thereon discharged sheets, second stack means for stacking thereon the sheets transferred from the first stack means, and a transfer unit for transferring the sheets from the first stack means to the second stack means. Further, the device includes transfer control means for driving, when a size of the sheet is equal to or smaller than a predetermined size, the transfer unit in a case where a first predetermined number of sheets are stacked on the first stack means, and for driving, when the size of the sheet is larger than a predetermined size, the transfer unit in a case where a second predetermined number of sheets smaller than the first predetermined number of sheets are stacked on the first stack means.
In still yet another embodiment, the sheet process device of the present invention comprises a transfer unit for performing sheet transferring from a first storage unit to a second storage unit, the first storage unit capable of storing plural sheets in a binding process to the sheets and plural sheets in a non-binding mode not to perform the binding process, and controlling means for controlling the transfer unit. In addition, in a case where an operation mode is the binding mode, the controlling means causes the transfer unit not to perform the sheet transferring before all the sheets included in one group are stored in the first storage unit, but to perform the sheet transferring after all the sheets included in the one group are stored in the first storage unit. Further, in a case where the operation mode is the non-binding mode, the controlling means causes the transfer unit to perform the sheet transferring before all the sheets included in the one group are stored in the first storage unit.
In still yet another embodiment, the present invention provides a control method for a sheet process device which comprises a transfer unit for performing sheet transferring from a first storage unit to a second storage unit, the first storage unit capable of storing plural sheets in a binding mode to perform a binding process to the sheets and plural sheets in a non-binding mode not to perform the binding process. More specifically, the method comprises a controlling step of controlling the transfer unit, wherein, in a case where an operation mode is the binding mode, the controlling step causes the transfer unit not to perform the sheet transferring before all the sheets included in one group are stored in the first storage unit, but to perform the sheet transferring after all the sheets included in the one group are stored in the first storage unit. In addition, in a case where the operation mode is the non-binding mode, the controlling step causes the transfer unit to perform the sheet transferring before all the sheets included in the one group are stored in the first storage unit.
In still yet another embodiment, the sheet process device of the present invention comprises a transfer unit for performing sheet transferring from a first storage unit to a second storage unit, the first storage unit capable of storing plural sheets from an upstream side, and controlling means for causing the transfer unit to perform the sheet transferring when the number of sheets stored in the first storage unit reaches a reference value. In addition, the reference value in a case where the sheets in a group composed of the plural sheets of a first size are stored in the first storage unit is smaller than the reference value in a case where the sheets in a group composed of the sheets of a second size smaller than the first size are stored in the first storage unit.
In still yet another embodiment, the sheet processing method of the present invention provides a control method for a sheet process device which comprises a transfer unit for performing sheet transferring from a first storage unit to a second storage unit, the first storage unit capable of storing plural sheets from an upstream side. More specifically, the method comprises a controlling step of causing the transfer unit to perform the sheet transferring when the number of sheets stored in the first storage unit reaches a reference value. In addition, the reference value in a case where the sheets in a group composed of the plural sheets of a first size are stored in the first storage unit is smaller than the reference value in a case where the sheets in a group composed of the sheets of a second size smaller than the first size are stored in the first storage unit.
In still yet another embodiment, the sheet process device of the present invention comprises aligning means for aligning sheets from an upstream side at any one of plural aligning positions including a first aligning position and a second aligning position on a first storage unit, and controlling means for causing, in case of aligning the sheets of a first group at the first aligning position on the first storage unit, the aligning means to align the sheets of a second group subsequent to the first group at the second aligning position. In addition, the controlling means operates the aligning means such that the distance between the first aligning position at which the sheets of the first group are aligned and the second aligning position at which the sheets of the second group are aligned in a binding mode to perform a binding process to the sheets is made different from the distance between the first aligning position at which the sheets of the first group are aligned and the second aligning position at which the sheets of the second group are aligned in a non-binding mode not to perform the binding process.
In still yet another embodiment, the sheet processing method of the present invention provides a control method for a sheet process device which comprises aligning means for aligning sheets from an upstream side at any one of plural aligning positions including a first aligning position and a second aligning position on a first storage unit. More specifically, the method comprises a controlling step of causing, in case of aligning the sheets of a first group of the first aligning position on the first storage unit, the aligning means to align the sheets of a second group subsequent to the first group at the second aligning position. In addition, the controlling step operates the aligning means such that the distance between the first aligning position at which the sheets of the first group are aligned and the second aligning position at which the sheets of the second group are aligned in a binding mode to perform a binding process to the sheets is made different from the distance between the first aligning position at which the sheets of the first group are aligned and the second aligning position at which the sheets of the second group are aligned in a non-binding mode not to perform the binding process.
Other objects and features of the present invention will become apparent from the following detailed description and the accompanying drawings.